Allodynia is a rare type of pain, generally on the skin, that’s caused by something that wouldn’t normally cause pain. This pain type is frequently associated with , and some people withhave it as well.
Other conditions associated with allodynia include (shingles), and . Outside of these conditions, allodynia is a rare symptom.
Knowing this term may help you communicate better with your doctors and other health-care providers as well as with understanding research about your illness.
Allodynia comes in three different and distinct forms. It’s possible for you to have one, two, or all three kinds.
The different forms are:
- Tactile allodynia: Pain caused by touch. This can include clothing lying against the skin (especially the tighter parts of clothing, such as waistbands, bra straps or the elastic part of socks,) a hug, or someone touching you lightly on the arm.
- Mechanical allodynia: Pain caused by movement across the skin. This can be a towel as you dry yourself off, bedsheets brush against you, or even the air from a fan blowing moving over your skin.
- Thermal (temperature-related) allodynia: Pain caused by heat or cold that is not extreme enough to cause damage to your tissues. Your hands and feet may burn if they get chilled, or getting too hot may make them ache. (However, if your hands and feet turn blue when they’re cold, talk to your doctor. This may be a symptom of a different condition called , which can lead to tissue damage.)
It’s often hard for people, even those who experience allodynia, to understand how these otherwise harmless things can cause so much pain. However, it is a real pain and doesn’t mean that you’re crazy or making too big a deal out of “normal” aches and pains.
Allodynia is different from hyperalgesia, which is the mechanism that “turns up the volume” on pain in these conditions. Hyperalgesia takes your pain and makes it worse, while allodynia is an actual type of pain.
Allodynia is believed to be a hypersensitive reaction to stimuli. Research suggests that it may result from something called , which is believed to be an underlying mechanism of fibromyalgia, chronic fatigue syndrome, and . “Central” indicates the central nervous system and “sensitization” means that it’s become extra sensitive.
The pain signals of allodynia come from specialized nerves called . The job of nociceptors is to sense information about things like temperature and painful stimuli right from the skin. Most nerves have to send signals to the brain and wait for the brain to send a signal back before they respond. Nociceptors don’t have to do that—they react immediately based on what they detect. That’s what allows you to pull your hand away from something hot before you get burned, often before you consciously perceive the heat.
When these nerves become sensitized, they start interpreting all kinds of sensation as pain. Again, this is real pain that has just as much of an impact on you as any other source of pain.
Living With Allodynia
Allodynia can make your life difficult. Something as simple as wearing a shirt may become painful, or even agonizing. Many people who have allodynia find that they need to.
Thermal allodynia can play a role in another one of our symptoms: . To manage it, you may need to do things like dressing in layers or moving your work station away from vents that blast you with hot or cold air. You may have to learn how to
Most of the common drug treatments for these illnesses can help alleviate allodynia along with other types of pain. These include:
Tricyclic antidepressants such as
A lot of us also get some relief with topical painkillers, such as lidocaine, BioFreeze, , and Aspercreme.
It’s possible for to make allodynia worse, so it’s important to find a massage therapist who understands your condition and knows how not to aggravate this symptom.
A Word From Verywell
The conditions associated with allodynia are often chronic and difficult to treat. You may not ever be completely free from the pain, but by working with your doctor and making appropriate lifestyle changes, you may be able to minimize its impact on your life.